Portable compressor



Patented ele. 13s, i923 noiunnrcooonrr, or eoivsranrnvornn, TURKEY, Ann Manent. rnn'ror, or nonsense, rennen.

PGRTABLE CQMPRESSOE.

Application filed Getber 25, 1919. Serial No. 333,229.

To all whoml t may concern.'

Be it known that we, DOMENICO Courir, citizen oil the Kingdom of Italy, and Man CEL Pniror, citizen ol the French Republic,

5 and residing at 68 Muhurdar Djadessi, Moda-Kadilreuy, Constantinople, Turkey, and et Bue clfldsace, Mulhouse, France, have invented certain new and useful Improvements in Portable Compressors (for which l we have filed application in Francey Sep# tember 3, 1918, Patent No. 497,208), o'f which the following is a specification.

The present invention consists in a single cylinder, singlepiston high speed air coral l pressor which compresses the air `in twophases. The rst compression off the air is leffected by one of the faces of the piston in 'r the crank casing, Whilst the iinal compres'-v sion is effected in the cylinder under the 2O action of the other face ofthe piston.

Two forms of construction of the coinpressor which constitute the invention are illustrated more or less diagrammatic-ally inv vertical section and by way of example in Figs. 1 and 2 of the accompanying drawing.

The cylinder l of the compressor (Fig. 1) is mounted on an impermeable crank casing 2 through which a sha-ft 3 runs that carries the crank 4, which actuates the` piston 6 through the medium of the connecting rod 5. A suction valve 7 is mounted ata suitable point in the crank casing 2 which has formed in it at another suitable point an opening 8 over which a tube 9 is mounted which is connected with the opening-'T10 at a point in the cylinder situated immediately above the upper face ofthe piston when the latter is at the lowest point ot its course.

A suction valve 11 identical with the valve 7 and a valve crown or cap 12 containing a compression valve 13 are arranged in the upper part ot the cylinder. The cap 12 carries the pipe 14 through which theV compressed air issues.

The apparatus thus constituted acts in the following manner: rlhe shaft 3 being actuated by any suitable motor, the piston 6 occupying the position shown that is to say that it has reached the end of itsv course in the cylinder 1. ln descending the piston 6 has created a suction behind it. The

valve 11 has'opened and the cylinder has filled with air at the atmospheric pressure. it the saine time it has compressed in the crank casing 2 the air contained and the valve 7 has closed. A volume of the cylinder and K that of the crank Casing when the piston has reached the bottom et its course there will be on the one hand above the piston a volume ot air V at atmospheric pressure P0, and on the other hand below the piston a volume Vfl-'l brought to the volume K and thel pressure of which consequently willbe 1350 Pa. fit the moment whenH the piston arrives at the lowest point in' its course it frees theopening 10. Thus the air will pass through the opening S and the tube 9 from.

the crank casing into the cylinder above the piston 6 and a pressure Pm will be established that is less than Pm loutg-reater than Paz.

llVhen the piston moves up again it covers the opening 10 and isolates the cylinder (upper part) from. the cranlr casing. 'It

lcompresses once more the air that is above its upper face and the cornpressed`\V air escapes lthrough the valve 13, the cap 12 and the `tube 14. 0n the other hand the piston which moves up causes a suctional effect behind it in the crank casing 2 and in the lower part ot the cylinder 1. llllhen the lf V be taken as the pressure has become lowered, in this space,v

below Pa, t-heyvalve 7 will open and allow a fresh quant-ity of air to enter the crank casing. This air will be compressed when the piston descends again. The double cycle is thus reproduced during the working of.

the apparatus.v

in comparing this arrangement with anpressure Pa. But the arrangement that constitutes the invention then receives in its cylinder a quantity of supplementary air ata pressure that is variable according to the value ot the volume K so that at last the cylinder contents is 'fully equal to V but the pressure of the air therein will be greater than Pa. The `capacity ol. this new arrangement is thus greater than that of the inder above the upper face of the piston de-k pends on the ratio of the volume l of the crank casing and of the tubular piece 9 to the volume V of the cylinder. The greater the volume K in relation to the cylinder the smaller will be the valve of `the final precompression. @n the contrary this value will increase in proportion as li diminishes, the lower limit of K being determined. by the necessities ot the construction (situation o'l the connecting rod, of the crank, etc). The apparatus which has linst been described is mounted in the 'form of a compression group comprising two compressing cylinders and two driving cylinders with two stroke cycle explosions mounted on the saine shait, on a single frame or chassis so that the Whole easily portable. The driving cylinders form a block, one compressor being placed at each end of the shaft, the different devices necessary 'for the action et the group being included: magneto, carburetter, radiator, starting device, oil and water pumps, pretol and oil reservoirs, ilywheel, etc.

The groupis formed principally for boring mine holes, for war purposes but is also applicable to removable installations or installations of a temporary character for which it suitable in consequence of its slight weight and its simplicity.

It should be clearly understood that the compressing engine which constitutes ythe invention may be utilized tor the compression o'l' gases other than air that there may be any number ot cylinders and that tbe compressing pistons may be actuated by a .iotor of any kind, that the valves may be operated mechanically, the cylinder ends not set in.

rlhe connection between the crank casing and the cylinder may be effected by a tube `9 connecting the crank casing in the upper part of the cylinder with a valve cap or crown containing a valve l5, as shown in Fig. 2.

rlhe working is thus as follows:

The piston 6 in descending createsa suction. rlhe valve l1 opens and the gas is compressed in the crank casing. The spring acting on the valve l5 is arranged so that this valve opens lwhen the pressure in the. crank casing attains a value approximating to the pressure Pm and the phenomena described above are reproduced.

The arrangements, described above may also be applied to a compressor working at any speed whatever.

The drawing in of the air introduced below the piston may be effected either by means of an automatic valve or a mechanically operated valve mounted on a space or receptacle which communicates withL the crank casingv or the lower part or' the cylinder or through an opening formed in the lower part of the cylinder in the crank casing or in any device whatever that cornmunicates with the lower part of `cylinder or with the crank casing. The. opening may be alternately freed and obstructed by the piston itself or by any other mechanism whatever. y

`What we claim is: f

ln a two stage air compressor a cylinder having its head end adapted for high com- -J pression and its crank endy adapted for low compression, a crank case closing the crank end, a piston adapted to be reciprocated in said cylinder, an inlet valve in the head of` the cylinder, an exhaust valve in the head oit the cylinder', an inlet valve 1n the crank case` a pipe connecting the'v crank case with the'` head end of the cylinder, and a valve inthe head ol" the cylinder adapted to admit air thereto from the crank case when the pressure in the crank case exceeds a predetermined limit.

ln testimony whereof we aiiiX our signatures in presence of two witnesses. a

ING. DOMENCO @ORPI MARCEL PRTOT.

lVitnesses JOHN Voi/Hon, .y .Y PAUL CoULoMB. 

